Adventitial Cystic Disease

Adventitial cystic disease occurs when a cyst in a blood vessel restricts or blocks blood flow. It usually affects the popliteal artery in the back of your knee. Common symptoms include lower leg pain and cramping, especially during exercise. Sometimes, cysts go away on their own, but surgery is usually the most effective treatment.


What is adventitial cystic disease?

Adventitial cystic disease is a rare condition in which a cyst (fluid-filled sac) forms in an artery or vein. The cyst forms in the adventitia, which is the outermost wall of your blood vessels. The cyst can block blood flow in your artery or vein, especially during periods of movement or exercise.

The condition usually affects the popliteal artery, which supplies blood to your knee and muscles in your lower leg. In about 15% of cases, cysts form in blood vessels other than your popliteal artery.

Who does adventitial cystic disease affect?

Adventitial cystic disease is most common in men and people assigned male at birth (AMAB) between the ages of 40 and 50. Men are five times more likely than women (and people assigned female at birth) to develop the condition.

It tends to affect otherwise healthy, active people. There’s no evidence to suggest that risk factors for other vascular diseases, such as obesity or high cholesterol, increase a person’s risk for adventitial cystic disease.

How common is adventitial cystic disease?

Adventitial cystic disease is rare. It makes up about 0.1% of all vascular diseases.


Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy

Symptoms and Causes

What are the symptoms of adventitial cystic disease?

The most common symptom of adventitial cystic disease is intermittent claudication. Intermittent claudication is muscle cramps or muscle pain due to reduced blood flow. It usually happens when you move or exercise and goes away when you rest. A lot of people with the condition have calf muscle pain. It usually just affects one calf, but in rare cases, it affects both legs.

If a cyst forms in a vein (rare), swelling may occur.

What causes adventitial cystic disease?

Experts have a few theories about what causes adventitial cystic disease, including:

  • Cells likely to cause cysts may enter blood vessels during fetal development.
  • Certain connective tissue disorders might cause cysts to form in blood vessels.
  • Some people may be more likely to develop cysts near joints.
  • Trauma or repetitive stress may damage parts of the blood vessel, leading to cysts.

There’s no evidence suggesting that adventitial cystic disease results from cardiovascular disease.


Diagnosis and Tests

How is adventitial cystic disease diagnosed?

It can be hard to diagnose because adventitial cystic disease tends to affect otherwise healthy people without risk factors for vascular disease. If you experience pain in the back of your knee or calf during periods of exercise, talk to a healthcare provider.

Symptoms of adventitial cystic disease might be similar to other vascular conditions, such as popliteal artery entrapment syndrome (PAES) or chronic exertional compartment syndrome. Your provider will rule these out before making a diagnosis.

Your provider may check the pulse in your foot and popliteal artery (behind your knee) during a physical exam. There might be a blood flow blockage if your pulse is hard to detect, especially when bending your knee.

Other tests for adventitial cystic disease that your provider may order may include:

  • Ankle-brachial index (ABI) to check blood pressure in your lower legs.
  • CT angiogram to evaluate blood flow and identify blood vessel blockages.
  • Duplex ultrasound to create a moving image of blood flow through your legs.
  • MRI to show cysts in or around the blood vessels.

Management and Treatment

How is adventitial cystic disease treated?

Sometimes, adventitial cysts go away on their own. However, cyst removal surgery is usually the most effective treatment. In some cases, your provider may recommend aspirating (draining) the cyst with a needle. Cyst aspiration is less invasive than surgery, but the cysts tend to come back.

A surgeon removes the cyst and any damaged parts of your artery or vein during cyst removal surgery. A severe condition (for example, when the blood vessel is mostly blocked) may require a different procedure. Your provider may use a vein graft (a piece of a vein from elsewhere in your body) or a synthetic patch to repair the blood vessel and restore blood flow. Bypass surgery to reroute blood flow around the blocked blood vessel may also be an option.



How can I prevent adventitial cystic disease?

There’s no way to prevent adventitial cystic disease. Talk to your healthcare provider at the first signs of leg pain, pressure, cramping or swelling.

Outlook / Prognosis

What is the outlook for adventitial cystic disease?

With any treatment for adventitial cystic disease, there’s a possibility that the cyst can come back. Long-term monitoring with imaging exams is usually necessary after treatment. However, most people found relief from cramps or pain after cyst removal surgery. One limited study found that cyst removal with vein grafting resulted in the lowest risk of cyst recurrence.

Living With

What questions should I ask my healthcare provider?

If you have adventitial cystic disease, you may want to ask your provider:

  • Are there ways I can reduce leg pain when I exercise?
  • How can I reduce the risk of the cyst coming back after treatment?
  • Is there any risk of developing a blood clot?
  • Will I need surgery to remove the cyst?
  • Will the cyst go away on its own without treatment?

A note from Cleveland Clinic

Adventitial cystic disease is a rare condition in which a cyst forms in a blood vessel and blocks blood flow to muscles. It usually affects the popliteal artery in your lower leg. Pain or cramps in your lower leg, especially during exercise, are the most common symptoms. Cyst removal surgery is usually the most effective treatment.

Medically Reviewed

Last reviewed by a Cleveland Clinic medical professional on 08/03/2022.

Learn more about our editorial process.

Appointments 800.659.7822